Automatic electric-lamp lock.



y izrmm D. L. CALAHAN. AUTOMATIC ELECTRIC LAMP LOCK. APPLICATION FILED 050.8. 1915.

Patented July 25, 1916.

Witnesses Attorneys grniar enrich.

DELGNA L. CALAHAN, 0F FAIRFAX, WASHINGIGN, ASSIGNOR OF ONE-THIltD T0 ROBERT D. MOORE AND CINE-T351311 T0 ROBERT E. ROBERTS, BOTH 0F FAIRFAX,

"WASHINGTON..

lhUTOMATIC ELECTRIC-LAMP LOCK.

Fairfax, in the county of Pierce and State J of Washington, have invented new and useful Automatic Electric'Lamp Look, of

which the following is a specification.

The present invention is a device for locking an incandescent lamp to its socket, to prevent the theft or removal oi'the lamp'or bulb without breaking or destroying the same so as to render the lamp useless.

It is the object of the'lnvention to provide a novel yet simple arid efiective means in a lamp socket for locking the plug of the lamp within the socket member to prevent the loss of the lamp, the locking means becessible and being readily exposed when the bulb is broken, in order that the plug of a burnt out lamp can be removed for the sub,- stitution of a new lamp.

. The loss of electric lamps by theft in fee tories, mills, public buildings and the like, amounts to a considerable item, but with the use of sockets embodying the present impovements, this loss will be eradicated, since the lamps cannot be removed without breaking the bulbs thereof, and which would naturally prevent-the thefts of the lamps, the lamps being readily replaced when they are burnt out,

The invention resides in the provision of a spring catch or pawl applied to the socket member of the lamp socket for holding the plug of the damp therein, the provision of an opening in the shell of the socket for exposing the catch so that it can be manually released, and the provision of a cull or collar normally concealing said opening and held in place by the bulb of the lamp, so that said cutl' cannot be removed until the bulb is broken. Thus, when the plug of the lamp. is threaded into the socket member, the catch engages the plug to prevent the unscrewing thereof, and the bulb of the lamp will retain the cuff in position, whereby said cull cannot be withdrawn from the shell of'the socket until the bulb is broken. This can readily be done when the lamp is burnt out, and the cull in being removed will permit an implement to be inserted through the opening of the shell, for releasing the catch,

so that the holder plug can be unscrewed Specification of Letters Patent.

Application filed December 8, 1915. Serial No. 65,744.

mg normally concealed so as not to be ac-' member-2 so that the spur 4 Patented Jul 25, ions.

and removed for the substitution of a new lamp. I

It is also within the scope of the invention to provide a locking device of the nature indicated which can be provided in a simple and convenient manner upon ordinary lamp sockets, as well as new ones, without requiring any changes inthe construction of the lamp socket itself or entailing prohibitive trouble or expense.

With the foregoing and other objects in view which will appear as the description proceeds, the "invention resides in the combination and arrangement of parts and in the detailsof construction hereinafter described and claimed, it, being understood that changes inthe precise embodiment of the invention herein disclosed can be made within the scope of what is claimed without departing from the spirit of the invention.

The invention is illustrated in the accompanying drawing, wherein Figure l is a side elevation of a lamp socket and lamp in locked position, the cuff being shown insectiofn. Fig. 2 is a cross section on the line 2-2 of Fig. 1. Fig. 3 is a fragmental elevation of the lamp showing the plug provided with an aperture for the engagement of a catch. Fig. l is a plan view of the catch. Fig. 5 is a plan view of an implement which is preferably used in connection with the lock.

In the drawing, there is illustrated an ordinary lamp socket embodying a metallic shell. 1 inclosing the threaded socket member 2 as usual.

In carrying out the invention a spring catch 3 is applied to the socket member 2, said catch being in the form of a leaf spring extending through an arc of over 180, and provided at one end with a hookshaped spur or pawl l. The catch 3 is snapped onto the socket member 2 so as to embrace thesame and lie within the groove of the thread of the said socket member at the proper point, and an aperture 5 is punched in the socket projects in 'wardly through said aperture.

The shell 1 of the socket is provided with an opening (3 adjacent the socket member 2 and exposing that .end of the catch 3 hav ing the spur l, in order that said spur can be pur 4 is engageable in an aperture 7 punched in the shell of the plug 8 of the lamp or bulb 9, whereby when the plug 8 is screwed into the socket member 1, the spur 4 will spring into the aperture 7 when the lamp is screwed home, to thereby pre vent the unscrewing of.the lamp from the V socket.

In order to normally cover the opening 6 to prevent access being had to the catchof the look, a cuff or collar 10 is slipped onto thegshell 1 around the socket end thereof to cover the opening 6, and the outer end or the cuff 10 is contracted, as at 11, to bear against the bulb ofthe lamp, whereby said bulb holds the cull 10 in place upon the shell.

' The implement illustrated in Fig. 5 is preferably used in connection with the lock, and embodiesa shank 12attached to a suitable handle. 13 and having a flattened head 14 provided with an open slot 15 and-a p e 4 1 The socket can be readily provided'with the improved features, since the catch 3 can be'ieadily placed upon the socket member 2 before the shell '1 isappl-ied, the aperture 5 being readily punched in the socket member .215 means of the point-16 ef the implement.

The aperture7 is also punched in the plug 8 by means of the. point 16 of the implement,

v and the cufl 10 is then placed upon the shell 1'. Then, when the plug of the lampis --threaded into the socket member 2, it will force the spur 4: outwardly. until the aperture 7 reaches said spur, in which event the '"spui t'will spring into the aperture 7. The

locking means is in the form of a ratchet device to permit'the plug to be. screwed into.

the socket member, but to prevent the plug from being unscrewed, it being noted that the spur 4 is of hook-shape so that it will efiectively prevent the unscrewing of "the plug. The spur 4 in'projecting through the aperture 5 Wlll hold the catch 3 in place -relative to-the socket member, and the bulb-of.

the lamp will hold the cufi 10 upon the shell 1, and prevents access being bad to the catch 3. It is thus impossiblefor a mali-- ciously inclined person to remove the lamp. for purpose of'theft or otherwise, unless the I bulb of thelamp is broken.

the bulb is broken, thereby releasing the To renew the, lamp when 1t is burnt out,

cufl 10 so that said cufi can be withdrawn from the shell 1. This enables the point 16 of the implement to beiinserted' through the opening 6ffor prying up the end of the catch 3, to retract the spur 4 from the plug 8.

If desired, the spur tca'n be moved to one 'side to'rest against the periphery of the socket member '2, and the implement can then be used as a wrench for unscrewing the plug, the slot 15' being engaged with the flattened terminal 17 of the filament supporting tube 18 which. projects from the plug, said tube being exposed due to the .ln'eaking of the bulb. The implementmay thus be used as a Wrench for unscrewing the plug conveniently and without danger. After the plug is removed, the catch is replaced, as well as the cuff 10, and a new lamp can be screwed into the socket as before, the aperture 7 being provided in the plug of the lamp before it 1s screwed in place.

Having thus described the invention, what is claimed as new is:

1. In a lamp socket, a shell, a socket mem- 7 her therein having a plug engaging "catch, said shell having an openln 'exposing said catch, whereby the catch 'can be released, and means held in place'by the bulb of a lamp for covering said opening and concealing said catch.

lying within the groove thereof, the socket member having an aperture and one end of said catch having an inwardly projecting spur projecting through said aperture to engage a lampp lug for preventing the uning exposing that end of the catch having .said spur, and a cufl adapted to he slipped upon the shell to cover said opening and to be held in place by the bulb of the lamp.

' screwing thereof, said shell having an opena In testimony that'I claim the foregolng as my own, I have hereto aflixed my signature.

inthepresence of two witnesses,

DELONA CALAHAN.

' Witnesses: p Lnw Brown,

C. R. SAVAGE. 

